This invention relates to a novel molding composition, a method for its preparation and its use in the manufacture and repair of dentures and the taking of dentate impressions. More particularly it relates to a settable laboratory putty.
The use in the dental field of molding compositions such as settable thiol polymers, silicone rubber polymers, cementious compositions and the like is known. This use, in general, is subject to drawbacks and inconveniences. For example, molding compositions containing thiol polymers are usually malodorous and, like conventional molding materials prepared from silicone rubber precursors, their use in denture work involves premixing of a tacky liquid with a suitable setting catalyst using a spatula or the like. Undesirable sticking of mold components to denture components in denture manufacture and repair often makes necessary undercutting and chipping away of adhering molding composition, for example cement, from the denture. Conventional practice includes introduction in a denture mold of spillways for the withdrawal of excess acrylic or epoxy denture-forming compositions. These spillways, vents, etc. leave spurs, ridges and the like in the shaped denture which must be removed in a manner providing at least a reasonable fit for the wearer in that area. These operations all increase the cost and time involved in the manufacture and/or repair of a denture, and the quick facile production of a perfectly fitting denture is, more often than not, the exception rather than the rule.
It is an object of this invention to provide a settable molding composition suitable for use in the manufacture, or repair of a denture which (1) can be effectively used in connection with wax impressions and cementious solids and denture components without problems of undesirable adhesion or the use of spacer materials and the like, (2) does not require the introduction of spillways, vents and the like for the flushing of excess denture-forming materials, epoxy or acrylate resins or the like, from a mold prepared therefrom, (3) results in the production of a true fitting denture without the grinding, buffing, etc. normally involved in removing spurs, ridges and the like produced by spillways or vents in a denture mold, and (4) may be conveniently and directly combined with a suitable setting catalyst by hand kneading the catalyst into the composition without intermediate spatulation or the like. These and other objectives and the satisfaction thereof will be clear from the examples and descriptions to follow.